We present the clinical and hemodynamic profile of 33 patients, older than the 18 year with tetralogy of Fallot. Cardiac catheterization and selective angiocardiography were performed in all cases. We excluded patients with valvular pulmonary atresia associated with tetralogy of Fallot. Most of the patients were in functional class II or IV of the New York Heart Association and all presented with cyanosis. In the electrocardiogram of 23 patients we found right bundle branch block. None had significant cardiomegaly, 19 of 20 cases had reduced pulmonary blood flow and reticular pattern in the lung fields as observed in the chest X-ray. We did not find correlation between the age and the degree of cyanosis, but the level of arterial desaturation correlated with the functional class. The right ventricular systolic pressure was elevated in all patients. In all cases but one the pulmonary arterial systolic pressure were normal of slightly increased. One case with mild pulmonary infundibular stenosis had pulmonary systolic pressure similar to the systemic pressure. Multivariate analysis for functional class showed significant value for cyanosis. Systemic-pulmonary shunt was performed in 10 patients with hypoplastic pulmonary arteries plus reduced pulmonary blood flow, with one postoperative death. We did not find postoperative mortality in patients who underwent corrective surgery. The anatomic and functional behavior of patients who underwent surgery, allowed better tolerance to their heart defects.